Getting warmer in attempt to reach ignition

Fusion energy output hits modest milestone

ALIGNING THE TARGET Workers perform maintenance on the National Ignition Facility’s target chamber. When devoid of people, this is where 192 laser beams fire simultaneously at a gold cylinder containing a capsule coated in hydrogen fuel. The positioner that holds the cylinder steady is at right.

Lawrence Livermore National Laboratory

A quick-hitting laser pulse has breathed new life into a multibillion-dollar effort to generate substantial amounts of fusion energy.

The 192 laser beams at the $3.5 billion National Ignition Facility have now triggered fusion reactions that briefly sustain themselves. The reactions, reported February 12 in Nature, produced nearly 10 times as much energy as the previous record for laser fusion research. But they still fall well short of recouping the energy supplied by the world’s most powerful laser.

“It’s a very important milestone,” says Steven Rose, a plasma physicist at Imperial College London. “However, there are many other milestones to pass.”

In 2009, NIF officials at Lawrence Livermore National Laboratory in California were a far more confident bunch. Computer simulations had suggested that a NIF laser pulse could compress a layer of frozen hydrogen within a

This article is available only to subscribing members. Join the Society today or Log in.